Ok, here goes..... OP, I don't know how much hearing science background you have but it's all fairly straight forward and easy if you're used to it. If you need further explanation, feel free to ask. Also, please excuse the lousy photoshop skills and cell phone pictures.
Also, aud students, what have you been taught as far as fitting to max gain levels? I tend not to fit above about 30dB as I find most patients complain of ambient sounds too much. Any arguments to this?
So assuming primary F(0) of a lung being approximately 300Hz.....
Let's say we have three audio's. All very likely. On two of the audio's you'd be ok fitting RIC/RITE style devices with open domes because you don't care so much about gain below about 1kHz (essentially normal hearing). However, given the low frequency bleed on an open fit you'll lose ALL gain below 1k-1.2kHz without a mold. This is the same as building a subwoofer without a rear baffle if anyone ever tried it. That said, even if you bother to figure a way to stream the information to the aids alls you're going to get, if you're LUCKY, are 3rd harmonics starting around 1500Hz based on a 300Hz f(0). Ok, I realize it's actually going to be a 1400Hz harmonic. My shoddy mental math has run away for the night. But look where most of the dx information is (yellow). WELL below anything the aid will give you in the primaries of the asculatation. But it'd be completely inappropriate to occlude this person just for the sake of giving them heart sounds cause the rest of the fitting will fail.
On the third audio you need gain from 250 through 6kHz. Obviously on the third audio you could get low frequency gain any number of ways but lets just assume in this case the patient is a physician who uses a stethoscope regularly and prefers an ITE style device. IMO a Lyric or Soundlens device would probably be ideal assuming there's enough real estate in the canal as opposed to a traditional CIC. The nice thing about this loss is you'd be fitting for lows in the first place and not worry about occlusion. So you'd be getting the necessary gain <1kHz to pick up ddx from heart/lung sounds. That's why the "only" issues you'd need to worry about was getting the signal to the aids (streamer is fine, you guys are right) and physical fit (can be a bitch when device is fully seated past second bend).
I hope I've made that reasonably muddy. OP, that's why it's important to know the actual audio rather than just saying I've got a mild-mod SN loss.....
Making sense to anyone??